Mr Connell on the Chemical Constitution of Brewsterlte. 39 



and loss are nearly neutralized, and we obtain nearly the same 

 proportions of the constituents in relation to one another, as is 

 afforded by either of the actual results. The mean of the two 

 analyses is as follows : — 



Silica, 63-666 



Alumina, .... 17*492 



Strontia, 8-325 1 , -^- - 



Baryta, 6-749/ *^^^* 



Lime, 1-346 



Oxide of Iron, . . . -292 



Water, 12-584 



100-454 

 When we endeavour to ascertain in what atomic proportions 

 these constituents are combined, we find that the formula of 

 Berzelius^ in so far as respects the solid contents of the mine- 

 ral, comes near its constitution, if we substitute strontia and 

 baryta for lime and soda. The relative proportions of water, 

 however, afford a considerable obstacle to their accommodation. 

 In the above analysis, it will be observed that the proportions 

 of the baryta and strontia to one another, approach the ratio of 

 1 atom of the former to 2 of the latter. For, 



9-75 [atom baryta] : 13 [2 atoms strontia] : : ^fy : 8-666. 



— In one of my analyses, the proportions obtained bore almost 

 exactly that ratio to one another. 



If we substitute strontia and baryta for lime and soda in 

 Berzelius' formula, we get 



and if we multiply the whole by 3, we get 



2 Sr S' + B S^ + 1 2 A S^ + 24 A ^. 

 If we calculate this latter formula, or the preceding one, taking 

 Sr 2 at. Stron. + at. Bar. 

 B = 3 ' ^" ^'' 



Silica, 63-973 



Alumina, 16192 



Strontia, . 7*796 \ ,«.^.2 

 Baryta, . 6-846 / ^^^*^ 

 Water, 16-192 



99999 



